I believe you can set a 'idle device timeout' setting that will do
this...

Go to Devices and open the properties of the library, then select the
Timers tab:
  
Idle device timeout - The number of minutes before an idle device is
unmounted. This attribute only applies to SmartMedia, Silo, and shared
native jukeboxes with device sharing enabled. A value of zero disables
this feature, volumes will not be unmounted from idle devices.



> -----Original Message-----
> From: EMC NetWorker discussion 
> [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On Behalf Of Terveen, Frank
> Sent: Monday, November 30, 2009 12:36 PM
> To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
> Subject: [Networker] Auto unmount
> 
> Dear nw gurus
> 
> I use an I scalar 500 LTO 4 robot on Windows 2003
> NW744
> Is there a way to let networker auto unmount tapes when backup is done
> 
> met vriendelijke groeten / With kind regards
> 
> Frank Terveen
> --------------------------
> Sent via BB
> Disclaimer:
> http://www.afm.nl/disclaimer
> http://www.afm.nl/disclaimer_english/
> Indien u de link niet kunt openen, neemt u dan contact op met 
> telefoonnummer +31 (0)20 7972000. Meer informatie vindt u op 
> de website http://www.afm.nl.
> If you are unable to access the link, please dial +31 (0)20 
> 7972000 Additional information is available on the website 
> http://www.afm.nl.
> 
> To sign off this list, send email to 
> listserv AT listserv.temple DOT edu and type "signoff networker" in 
> the body of the email. Please write to 
> networker-request AT listserv.temple DOT edu if you have any 
> problems with this list. You can access the archives at 
> http://listserv.temple.edu/archives/networker.html or via RSS 
> at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER
> 

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER